Pipe line orifice flanges are conventionally found in various types of industrial installations including chemical plants, the petroleum industry and other various installations where high pressure lines are employed. Such orifice pipe line flanges are usually comprised of a pair of flanges welded to a pipe line. The flanges are adapted to be butted together and connected with an interior orifice plate held by the flange to provide a restricted orifice within the interior of the flange fitting. Such orifice plates may be of different diameter as will be readily understood in the art and are used for testing and measuring the fluid characteristics in a conventional fashion. Such flanges are usually provided with test plugs on both sides of the interior orifice plate in order that the upstream and downstream pressure may be measured or tested in one fashion or another.
The orifice flange fitting are further usually provided with break-away bolts. This is simply a threaded opening or the like in one flange receiving a bolt which can be tightened against a solid surface of the opposing flange to break the flange apart for repair or the like. The orifice flanges in the field are generally connected together by simple connecting bolts clamping the flanges tightly together and it will be understood that various types of sealant and gaskets are used to provide a sealed interface between the flanges.
It will be readily understood that such orifice flanges have in the past been subject to the usual wear and tear and failure in the field. When it is realized that such pipe line flanges are quite often very large and situated at remotely accessible areas the repair and maintenance can be quite difficult. The pipe lines involved are quite often very large and handle large quantities of fluid. Break-away and repair can involve a great amount of capital expenditure, time and labor.
By means of the instant invention there has been provided an orifice flange that can be simply employed in the field to pump sealant in the interface between the flanges to prevent any leakage therethrough. The flange clamp can be used on the existing orifice flange assembly without requiring breakdown. Thus when used in the field by a repair man the orifice flange can be maintained in operation for a long period of time until complete overhaul and replacement is desired.
This invention comprises a flange clamp which basically contitutes the pair of semi-cylindrical clamps which can be clamped over the orifice flanges with cut-outs to accomodate the conventional test plugs employed and without requiring of their removal. The semi-circular clamp further receives sealing ring halves which are adapted to be pressed into the interface between the flanges. A special sealing means is provided by an elongated member in the nature of a necked bolt threaded at both ends which is adapted to be fitted through a pair of opposed flange openings which normally receive a flange connecting bolt. The elongated member receives nuts at both ends so that it can be drawn tight against the pumping collar fitting over the elongated member at one end.
The pumping collar has a larger internal diameter than the external diameter of the elongated bolt-like member in such a fashion that a port which is adapted to receive a sealant pumping gun or the like can pass the sealant through the port and through the passage way defined by the necked outside of the elongated member and the interior of the pumping collar. The sealant then finds its way through a passage defined by the interior of the flange bolt hole opening and the exterior of the reduced diameter elongated member into the interface between the two flanges. The pumping collar is connected tightly against the exterior of the flange by nuts on both ends of the elongated member so that a sealed fit is provided for the pumping operation.
The orifice flange clamp of this invention is further provided with plug members which are adapted to plug the break-away bolt openings which are conventionally provided in the orifice flange assembly.
Thus by means of the instant invention there has been provided an orifice flange clamp which can be simply fitted over an orifice flange without requiring break-down or removal of the affected parts. The clamp once it is assembled can be simply used to pump sealant through the pumping collar and provide for tight seal of the orifice flange assembly so that break-away is not required and continuous operation can be provided. The use of the test plugs is not interrupted by the repair provided by the orifice flange of the instant invention and the entire clamping operation can be effected in the field at remote locations on an emergency basis without the requirement of complicated break-down and repair mechanism.
The above features of this invention and further objects will appear in the detailed description which follows and will be otherwise apparent to those skilled in the art. For the purpose of illustration of this invention there is shown in the accompanying drawings a preferred embodiment thereof. It is to be understood that these drawings are for the purpose of example only and that the invention is not limited thereto.